Quantitation of collagen in the wall of the human urinary bladder.

Abstract

Biochemical assay of detrusor muscle collagenous protein is of value in assessment of urinary bladder structure and function. Detrusor structural change may account for increase in bladder capacity during childhood, may account for relaxation of the urethrovesical junction prior to onset of voiding, and may occur secondary to repeated bladder infection. The present investigation consisted of hydroxyproline and protein nitrogen determinations of normal human bladder tissue removed at autopsy. No significant variation in collagenous or total protein composition of bladder detrusor muscle or urethrovesical junction was found with increasing age of autopsy subjects. Results suggest that changes in bladder capacity with age are due to neural maturation and not structural change. In addition the results support the concept that opening of the urethrovesical junction during induction of the micturition reflex is a passive sequential effect of detrusor contraction.